Sandoz and Momenta Pharmaceuticals of Novartis AG Group received FDA approval for its generic drug for multiple-sclerosis to be called ‘Glatopa’. The U.S. food and Drug Administration (FDA) gave approval for the first generic drug version of the block-buster ‘Copaxone’ by Teva Pharmaceuticals for multiple-sclerosis. The launch of the copycat drug is not announced yet.

As per analysts from Teva, Copaxone which is an injection is the company’s top selling and most lucrative product. Teva Pharmaceuticals known mainly for its generic drug class reported US$4.2 billion in revenue from Copaxone sales that accounted for 21% of the total revenue of the company.

Earlier in the year, the U.S. supported the decision for Teva’s patent for Copaxone not to expire until September 2015. However, a spokeswoman from Teva commented that the company has acknowledged a generic version of Copaxone to enter the market and has made room for it. As per another market research analyst, Teva has been quite open about the risk to Copaxone.

At the outset, Momenta’s shares jumped 6.1% on Thursday to be priced at US$17.08, while Teva’s dropped 3.8% to be priced at US$63.49. As per Sandoz, half a million population is affected from multiple-sclerosis in the U.S every year, and approximately half of the ones diagnosed are treated for the disease.

Glatopa is indicative of being more suitable for patients that have relapsing forms of multiple sclerosis, and including those that have had first clinical occurrence and have also had magnetic resonance features consistently with the disease.